objc:define-objc-class

(objc:define-objc-class name (superclass*) (slot-spec*) class-option*)

Defines name as a CLOS class that implements an Objective-C class. Beside the defclass options it takes (:objc-class-name "Name"), the Objective-C class to create; (:objc-superclass-name "Name"), its superclass when no Lisp superclass implements one (NSObject by default); (:objc-instance-vars ("name" type)...), instance variables read with objc:objc-object-var-value; and (:objc-protocols "Name"...), protocols the class adopts. With no superclass, the class inherits objc:standard-objc-object. A class that names no Objective-C class and inherits none is a mixin: its methods are installed on every subclass that names one. A class of that name this process defined before (a re-evaluated definition) is reused with its methods replaced; one Lisp did not define is refused. Part of the macOS-only objc package -- the interpreter (java -jar, or the rontolisp native binary), a compiled .class / .jar and a --native executable for macOS on Apple silicon, never a .wasm. The definition needs no runtime: the Objective-C side is made when the runtime is opened (objc:ensure-objc-initialized, or the first send). See the macOS GUI guide.

MY-APP> (define-objc-class my-object ()
          ((slot1 :initarg :slot1 :initform nil))
          (:objc-class-name "MyObject"))
MY-OBJECT
MY-APP> (define-objc-method ("areaOfWidth:height:" (:unsigned :int))
            ((self my-object)
             (width (:unsigned :int))
             (height (:unsigned :int)))
          (* width height))
"areaOfWidth:height:"
MY-APP> (invoke (alloc-init-object "MyObject") "areaOfWidth:height:" 6 7)
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